Revert 236150 "Disable Vsync when Aero Glass is enabled."

This seems to be causing issues with some windows not being updated.

> Disable Vsync when Aero Glass is enabled.
> 
> The vsync is unnecessary for ratelimiting or tear prevention, and can cause issues when multiple windows are displayed.
> 
> BUG=313104
> 
> Review URL: https://codereview.chromium.org/75723004

BUG=313104,321979,322203
TBR=jbauman@chromium.org

Review URL: https://codereview.chromium.org/83173010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236880 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236880